1. Field of the Invention
The present invention relates, generally, to handling of sheets of paper for book and notebook binding processes. More specifically, the present invention relates to automatic feeder mechanisms for feeding a plurality of sheets of paper into a hole punch machine.
2. Related Art
Hole punch machines are commonly used in copy-centers, print-shops, corporate audiovisual centers, and other facilities that are responsible for binding notebooks, books, convention booklets, and other information packages. These machines punch holes along one edge of the paper, for spiral binding, for example. An example of one such machine is the open-end punch produced by Performance Design, Inc. of Boise, Id. under the trademark of the Rhin-O-Tuff(trademark) HD 7000(trademark) paper punch unit. Such a paper punch and its punch die assembly are illustrated in FIGS. 1 and 2 and U.S. Pat. No. 5,771,768.
Such a hole punch machine (1) features a die assembly (2) with a longitudinal opening/slot (3) in the die into which the edge of a small stack of paper is inserted. Once the paper is in proper position, the punch machine is activated and the punch pins (not shown) are pushed across the slot through the paper to form the holes. The paper is then removed, preferably by being slid out an open end of the die assembly or by being pulled up out of the die assembly. The punched paper is stored elsewhere for further processing and binding. In general, the punching process may be said to include placing a plurality of papers (referred to hereafter as a xe2x80x9cstack of paperxe2x80x9d) into the die assembly in a direction generally perpendicular to the direction of punch pin movement.
Such a hole punch machine (1), and possibly others on the market or in the patent literature, would benefit from an automatic paper feed system that would remove the need for the user to manually feed stacks of paper into the paper punch and manually remove the stacks of paper from the punch after punching. Automating the paper-handling feature of such a paper punch machine greatly increases the efficiency of using the machine, and the consistency and accuracy of paper placement and punching.
The present invention comprises an automatic paper feeder for a paper hole punch machine. The automatic paper feeder repeatedly provides a selected stack of paper sheets to a hole punch die assembly. The preferred paper feeder may be easily retrofit onto a conventional paper punch that receives paper vertically. After punching of the stack, the paper feeder preferably automatically ejects each punched stack into a tray from which the paper may be later removed without interrupting the feeding and punching operation. Preferably, the paper being fed to the punch is stored generally vertically, is fed to the die assembly generally vertically, and is ejected from the punch machine generally vertically.
The preferred paper feeder comprises a picking mechanism that accurately separates a stack of paper from a larger pile of paper in a stocking area, and a mechanism for moving the stack of paper into the die assembly for punching. The preferred paper feeder also includes a mechanism for removing the punched paper from the machine for further processing. The preferred picking mechanism comprises a picking mechanism that includes intake rollers closely adjacent to, and moving with, a stabbing member, resulting in an accurate, economical, and predictable picking system. The preferred stabbing member is closely adjacent to paper stops that help control the location of the paper being advanced for picking, an arrangement that contributes to accuracy and predictability.
The invention may also include a reception tray for receiving the punched paper upon its exit from the hole punch machine, so that paper removal may be done only occasionally as needed or when the reception tray becomes full. This way, a large pile of paper may be stocked onto the feeder, and punched paper may later be removed for binding or other processing at a convenient time and in a convenient amount.
An object for the preferred paper feeder is to separate xe2x80x9cstacksxe2x80x9d of one or more sheets of paper or other material from a large pile of paper and sequentially insert them into the paper punch. The preferred feeder is designed to separate stacks of about 5-25 sheets, depending on the media and on adjustment made to the belt movement or paper stop mechanisms, and, typically, for conventional copy paper, a stack of 10-15 sheets of paper is optimum. A pile of about 2500 or more sheets of paper/media fits conveniently on the preferred feeder. Special features for efficient and accurate handling of the paper pile and of each stack of paper are preferably included in the paper feeder and reception tray, so that the stacks are handled in quick succession to match the speed of the paper punch, for example, in the range of about 18,000-30,000 sheets per hour. For the preferred paper punch, which may operate at about 35punch cycles per minute, the automatic paper feeding and large pile of paper stock offered by the invented system increases speed and improves accuracy of paper punching.